[Hospital statistics as tool in epidemiologic studies: heart failure in Trieste]

Since 1995, the reimbursement of hospital healthcare expenditure in Italy has been based upon the so-called Diagnosis Related Groups (DRGs). The DRG 127 includes all the cases in which the main clinical diagnosis is "heart failure or shock" and, therefore, it may be used to obtain epidemiological data concerning this syndrome. The analysis appears to be of relevance, since in the district of Trieste the phenomenon of progressive aging of the general population has already reached a very advanced phase.

In this study, we evaluated, using the database of the Sistema Informativo Sanitario Regionale, the epidemiological data and clinical outcome of patients hospitalized for DRG 127 in the district of Trieste from 1997 to 2000 (5514 hospital admissions and 69,236 days of hospital stay).

The DRG 127 accounted for 2.6% of the total hospital admissions and 4% of the total days of hospital stay; moreover, it was found to be the first cause of hospitalization for medical DRGs (18.8%) as well as the first cause of hospitalization and of the days of hospital stay for cardiovascular DRGs (27.5 and 40.5%, respectively). Seventy-two percent of patients admitted for DRG 127 were > 75 years. In 1997, a mean of 4/1000 inhabitants of the district of Trieste were hospitalized for DRG 127 (4.6 hospital admissions and 63 days of hospital stay/1000 inhabitants). Over the 4-year period, the number of hospital admissions for DRG 127 increased by 20.4%, the days of hospital stay by 11.1%, and the related healthcare costs rose by 36.7%. Most of the patients (89%) were admitted in Internal Medicine or Geriatric wards. By using suitable corrective factors, the prevalence rate of heart failure in 1997 was estimated at 6.4@1000 (< 65 years 1.8@1000, 65-74 years 10.3@1000, 75-84 years 22.3@1000, > or = 85 years 47.4@1000). On the basis of the first hospital admission, the incidence was estimated at 2.4@1000 (< 65 years 0.8@1000, 65-74 years 2.2@1000, 75-84 years 9.3@1000, > or = 85 years 20.4@1000). The in-hospital 1-, 2- and 3-year survival rates from the time of the first hospital admission for heart failure were, respectively, 92, 80, 68 e 56%. The most frequent etiology was ischemic heart disease (50%), followed by hypertensive (26%) and valvular (7%) heart diseases. Ischemic patients showed the worst prognosis and ischemic heart disease was associated with a 3-year survival rate of 44%. However, the prognosis was found to be significantly influenced by the age of the patients, independently of the disease etiology.

The analysis of the hospitalizations for DRG 127 in the district of Trieste may contribute to forecast the epidemiological scenario and the healthcare demand for heart failure that will occur in the next decades at a national level, and may be useful to plan effective models of integrated home-hospital care for the increasing number of affected subjects.